Remove cta-admin schedulinginfo subcommand

As discussed in the old ticket CTA-old#1106 (closed) the cta-admin si ls works now:

It takes > 5 minutes to print this:

pcvlado ~ > time cta-admin si ls
logical library vid                   tapepool vo media type vendor mount type tape capacity priority min request age files queued  bytes queued oldest job start time sleeping mount sleep time disk system slept for mount count                            
         IBM1L8   -                r_na61_mc_2  -          -      -          2             0      250           14400         6970 6735197017844            1660688642          false          0                     -           0                            
         IBM1L8   -                      r_ams  -          -      -          2             0      250           14400           96   68492174818            1660732240          false          0                     -           0                            
         IBM1L8   - r_alice_test_datachallenge  -          -      -          2             0      250           14400            6      31379088            1660734245          false          0                     -           0                            
         IBM1L8   -                r_lhcb_arch  -          -      -          2             0      250           14400           61   72385788515            1660737584          false          0                     -           0                            
         IBM1L8   -            r_backup_single  -          -      -          2             0      250           14400           11   62274867858            1660738863          false          0                     -           0                            
         IBM1L8   -                     r_dune  -          -      -          2             0      250           14400           28  107939847616            1660738923          false          0                     -           0                            
         IBM1L8   -                r_alice_raw  -          -      -          2             0      250           14400            4      20919392            1660738946          false          0                     -           0                            
         IBM1L8   -                     r_ntof  -          -      -          2             0      250           14400           70   11580691292            1660739503          false          0                     -           0 
         IBM1L8   -                   r_cms_mc  -          -      -          2             0      250           14400           11   20145773538            1660741586          false          0                     -           0 
         IBM1L8   -                   r_na62_1  -          -      -          2             0      250           14400            3   29462902236            1660742155          false          0                     -           0 

The idea behind the schedulinginfo command was to print what is the next tape that will be mounted per logical tape library.

Unfortunately, the tape VID is missing from the above output.

In order to for this to be usefull, I think what would be needed is to show just next 5 tapes per logical library in the order in which they are scheduled to be mounted. Only with --all option should full queue be shown.

Given that we have survived until now without needing this, I propose to remove this command from cta-admin and revisit this need when we have a new scheduled (using PostgreSQL).